Rotatable nut and washer assembly

ABSTRACT

A fastener assembly wherein a sheet metal nut is rotatably coupled to a frusto-conical washer. The nut has an inner threaded barrel portion for engaging a cooperating male fastener element and an outer barrel portion which is particularly shaped for engagement by a tool for rotating the nut. The inner barrel portion is spacedly nested within the outer barrel portion and the respective barrel portions are joined at the upper end of the nut. The lower end of the inner barrel portion extends through a central aperture in the washer and is loosely curled under the edge of the aperture to provide a retaining collar. Adjacent the lower end of the inner barrel portion and the retaining collar, the inner barrel portion carries a peripheral bearing ring having a smooth undersurface lying at a selected acute angle to the longitudinal axis of the nut. The bearing ring is formed from metal skived from the outer wall of the inner barrel portion and compacted into the said ring configuration. The washer embodies a cylindrical lip projecting from its upper surface adjacent the aperture therein, and said lip has a smooth inboard surface which is complementary to and confronts the undersurface of the bearing ring on the nut. The outer barrel portion of the nut also includes a peripheral skirt at its lower end which rotatably bears on the adjacent convex face of the washer. The nut and washer components are free spinning with respect to each other and the said fastener assembly provides for a markedly improved torque-tensile relationship when the nut is turned onto a male fastener element and the washer is tightened against the confronting surface of an apertured member through which the male element protrudes.

United States Patent Duffy et a1.

[54] ROTATABLE NUT AND WASHER ASSEMBLY [72] Inventors: William B. Duffy,Berkeley Heights;

Charles K. Fisher, Belford, both of NJ.

[73] Assignee: TRW Inc., Cleveland, Ohio [22] Filed: Mar. 8, 1971 [21]App]. No.: 121,636

3,016,941 1/1962 Coldrem... 151/38 3,087,371 4/1963 Orner ..85/32 R3,331,272 7/1967 Hanneman ..85/32 R 3,425,473 2/1969 Knowlton ..151/38FOREIGN PATENTS OR APPLICATIONS 929,807 6/1963 Great Britain ..85/32 R674,940 10/1929 France ..151/38 Primary Examiner-Marion Parsons, Jr.Attorney-Philip E. Parker, James R. O'Connor and Gordon Needleman 1 1May 2', 1972 [57] ABSTRACT A fastener assembly wherein a sheet metal nutis rotatably coupled to a frusto-conical washer. The nut has an innerthreaded barrel portion for engaging a cooperating male fastener elementand an outer barrel portion which is particularly shaped for engagementby a tool for rotating the nut. The inner barrel portion is spacedlynested within the outer barrel portion and the respective barrelportions are joined at the upper end of the nut. The lower end of theinner barrel portion extends through a central aperture in the washerand is loosely curled under the edge of the aperture to provide aretaining collar. Adjacent the lower end of the inner barrel portion andthe retaining collar, the inner barrel portion carries a peripheralbearing ring having a smooth undersurface lying at a selected acuteangle to the longitudinal axis of the nut. The bearing ring is formedfrom metal skived from the outer wall of the inner barrel portion andcompacted into the said ring configuration. The washer embodies acylindrical lip projecting from its upper surface adjacent the aperturetherein, and said lip has a smooth inboard surface which iscomplementary to and confronts the undersurface of the bearing ring onthe nut. The outer barrel portion of the nut also includes a peripheralskirt at its lower end which rotatably bears on the adjacent convex faceof the washer. The nut and washer components are free spinning withrespect to each other and the said fastener assembly provides for amarkedly improved torque-tensile relationship when the nut is turnedonto a male fastener element and the washer is tightened against theconfronting surface of an apertured member through which the maleelement protrudes.

14 Claims, 9 Drawing Figures Patented May 2, 1972 3,659,491

INVENTORS WILLIAM B. DUFFY CHARLES K. FISHER ATTORNEY BACKGROUND OF THEINVENTION 1 Field of the Invention The invention relates to coupled nutand washer assemblies, particularly assemblies of the type wherein thenut is of sheet metal construction and the components of the assemblyare freely rotatable relative to one another.

' 2. Description of the Prior Art The prior art includes numerouspreattached or preassembled nut and washer assemblies. In the earlierart one finds disclosures of integralnut and washer combinations andassemblies wherein the components are separately fabricated butnonrotatably coupled. Characteristic of the foregoing devices is thedisclosure of U.S. Pat. No. 2,761,349 (R. M. Heller) whereincombinations and assemblies of both sheet metal and headed componentsare depicted. While integral and fixed assemblies of the typeexemplified by Heller have made a recog nized contribution to the artwith respect to convenient handling by the user, simplification ofpackaging and shipping as compared with separate nuts and washers,reduction of the loss of washers to be used with nuts in giveninstallations, and effective insurance that the proper size and shape ofwasher is consistently available for use in a specified application; ithas likewise been recognized that in applying such parts to cooperatingbolts or studs and tightening same against a workpiece surface,excessively high torque must be applied to the nut to achieve a desiredtension on the bolt or stud in that continuous simultaneous rotation ofthe nut and washer, subsequent to engagement of the workpiece by thewasher, precipitates a markedly increased resistance to turning of thenut and thus an extremely rapid and highly undesirable applied torqueincrease. In addition, the edge of the washer scores and often gouges orcuts a groove in the confronting workpiece surface and the increasingresistance to rotation creates problems with respect to the peeling,rupturing and deforming of sealing elements when such elements aredisposed adjacent the undersurface of the washer.

Having recognized the aforementioned deficiencies in integral or fixedassemblies, designers later moved to eliminate same through thedevelopment of combinations wherein the washer element was capable ofrotation relative to the nut and wherein the latter component could beheaded or sheet metal construction and carry either a multiconvolutionthread of a standard type or a single helix thread engager, or a threadcutting or forming element for engaging an unthreaded stud. US. Pat.Nos. 2,943,661 (W. Stern), 2,851,079 (R. M. Heller) and British Pat. No.929,807 (United-Carr Fastener Corporation) contain pertinent disclosuresto which reference may be had for a clearer understanding of theadvantages to be derived from combinations wherein the components arerelatively rotatably coupled. Notwithstanding the fact that the lastmentioned Heller and Stern and United-Carr Fastener disclosures placedparticular emphasis on the merits of rotatable combinations with respectto the minimization of the risk of deformation or other damage tosealing means employed in conjunction with the parts disclosed therein,the fact remains that the extent to which that objective was realizedwas primarily attributable to the capacity of the disclosed nuts torotate independently of any coincident rotation of the washer subsequentto initial clamping engagement of the washer with the confrontingsurface of a workpiece. However, regardless of the-presence or absenceof a sealing element, the principal objective sought to be achieved inthe construction of rotatably coupled nut and washer assemblies is thereduction of the torque which must be applied to the nut to realize aspecified degree of tension on a bolt, screw or stud, etc., onto whichthe nut is turned. Thus it follows that a construction, particularlywith regard to the nut to washer connection, which renders thecomponents free spinning relative to one another and greatly reduces thepossibility of any continuing washer rotation subsequent to initialclamping of the washer against a workpiece surface. not only providesfor greatly improved torque-tensile relationship in the fastenerapplication but also even further minimizes the potential for sealerdeformation, even in situations wherein the bond between the sealingelement and the washer is weak or the sealing element per se isstructurally defective.

The principal motivating force behind the development of the presentlydisclosed device was to realize the aforemen tioned critical objectivethrough an improved rotatably coupled sheet metal nut and washerassembly. The extent to which that purpose has been accomplished can beappreciated by way of a more detailed inspection of the aforementionedpatents when considered in the light of the description of a preferredembodiment of the improved assembly which follows hereinafter.

SUMMARY OF THE INVENTION A fastener assembly of the type wherein a sheetmetal nut having inner and outer barrel portionsis rotatably assembledwith an apertured lock washer. The outer nut barrel portion includes aperipheral skirt which rotatably bears on the washer adjacent theaperture therein. The assembly is particularly characterized by animproved nut to washer connection ineluding a connecting collar on theinner barrel portion which is curled under the internal edge of theaperture in the washer, the washer having a recessed undersurface inwhich portions of the connecting collar are seated, and a peripheralbearing ring on the inner nut barrel portion disposed adjacent theconnecting collar and the washer aperture. The said bearing ring isformed from metal skived from the inner nut barrel portion and compactedinto the ring configuration. The bearing ring has a smooth undersurfacedisposed at a selectively predetermined angle to the longitudinal axisof the nut and the washer has a smooth surface adjacent the aperturetherein, which latter surface is complementary to and in confrontationwith the undersurface of the bearing ring. Thus, the connecting collarand bearing ring cooperate to maintain the nut and washer in an assemblywherein the said components are free spinning relative to one another.The said construction is particularly adapted to provide an improvedtorque-tensile relationship in effecting a coupling wherein saidfastener assembly is turned onto a cooperating male fastener elementprotruding through an apertured member and the washer is tightenedagainst the confronting surface of the member.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a top plan view of a nut andwasher assembly according to the invention;

FIG. 2 is a side elevational view of the assembly depicted in FIG. 1;

FIG. 3 is an enlarged view of a cross section taken on line 33 of FIG.1;

FIG. 4 is a view of the invention similar to FIG. 3 as applied to acooperating bolt to secure two overlapping apenured members which aredepicted fragmentarily and in cross sectron;

FIG. 5 is an enlarged transverse cross sectional view of the washercomponent;

FIG. 6 is a further enlarged view of the right side of FIG. 3 depictingthe improved nut to washer connection;

FIG. 7 is an enlarged side elevational view of a slightly modifiedembodiment of the washer component;

FIG. 8 is a plan view of a modified form of a nut and washer assemblyaccording to the invention; and

FIG. 9 is an enlarged view of a cross section taken on line 9-9 of FIG.8.

DESCRIPTION OF A PREFERRED EMBODIMENT A relatively rotatable nut andwasher assembly according to the invention includes a nut 2 drawn fromsheet metal and having an inner barrel portion 4 connected at its upperend through a web 6 to an outer, hexagonally shaped barrel portion 8which circumscribes the inner barrel portion in spaced multiconvolutionthread 22 of a standard type which is adapted for threaded engagementwith a cooperating bolt. Adjacent its lower end, the outboard wall 24 ofthe said inner barrel portion carries a peripheral bearing ring 26. Thebearing ring 26 is formed from metal skived from the outboard wall 24and compacted into said ring configuration during fabrication of thenut. Further, the bearing ring has a generally triangular configurationas is clearly seen in the cross sectional views of FIGS. 3, 4 and 6 andalso has a smooth, nonburred undersurface 28 disposed at a selectedacute angle to the longitudinal axis of the but. The'surface 28 isideally, but not necessarily, at an angle on the order of 45 to thelongitudinal axis of the nut or an engaged bolt in that tests haveindicated that, when the said under-surface is disposed at an acuteangle substantially less than 45, the frictional resistance totightening of the nut on a bolt rises appreciably in that theconfronting complementary surface of the washer to be describedhereinafter tends to clamp or jam the inner nut barrel against the boltshank to an excessive degree in what might best be described as a colleteffect. Immediately adjacent and below the bearing ring 26, the saidinner barrel portion terminates in a connecting collar 30 which,subsequent to nut formation and prior to coupling with the washer, liesgenerally parallel to the aforementioned nut axis.

As best seen in FIG. 5, the frusto-conical spring lock washer has acentral through aperture 32, a generally cylindriform lip 34 projectingupwardly from its convex surface adjacent the aperture 32 and a recess36 formed in its under or concave face adjacent the said aperture. Theinboard surface 38 of the lip 34 has a downwardly tapering, funnel-likeconfiguration and the recess 36 has a generally corresponding butinverted funnel shape and the said respective lip and recess surfacesintersect in a very thin circumferential rim 40 which in effect definesthe minor diameter of the aperture 32.

In effecting the assembly of the washer 10 to the nut 2, the initiallycoaxial collar 30 is inserted into the aperture 32 in the washer andthereafter flared outwardly whereby its terminal end is loosely curledunder the circumferential rim 40 and nested in the recess 36. Thus, theundersurface 18 of the skirt 16 is brought to bear against a localizedarea of the convex face 20 of the washer (said area being generally butnot necessarily always less than one-half the total area of said convexface), and the complementary smooth surfaces 28 and 38 of the bearingring and washer lip, respectively, are also placed in opposed orconfronting relationship. While the aforementioned nut to washerconnection is relatively loose to permit free spinning of the componentsrelative to one another, the connection is likewise effective tomaintain the components in assembly under normal conditions of usage, towit, during packaging, shipping and repeated applications to and removalfrom a cooperating bolt.

By having particular reference to FIG. 6, the reader will observe whatis considered to be an ideal nut to washer connection, i.e., one whereinthe nut skirt is in contact with the opposing surface of the washer butthere are slight gaps, on the order of .010 inch, between the surfaces28 and 38 of the bearing ring and washer, respectively, and .005 inchbetween the opposing portions of the collar 30, and the recess 36. Testsconducted to date indicate that the maintenance of the aforementionedspacing insures a freely rotatable combination and, what is equallysignificant, insures that the skirt 16 of the nut is always in contactwith the confronting washer surface to provide at least a minimal biasof the washer toward the engaged surface of a workpiece and effect aresultant locking tension on a cooperating bolt in a joint whereinrelatively low torque is applied to the nut incident to specifiedtorquing of the nut.

In a typical joint such as that depicted in FIG. 4, the improvedfastener assembly is applied to the shank of a threaded bolt 42 tosecure a first apertured member 44 to a second apertured member 46wherein the latter is usually the fixed or base member in the joint.When the nut is turned onto the bolt preliminary or even final to thepoint where the head 48 of the bolt is drawn against the remote surface50 of the second member 46 and the lower peripheral washer edge ispressed against the proximate surface 52 of the first member 44 underrelatively minimal clamping pressure or bias exerted on the washer bythe nut skirt, the washer thereupon ceases further corresponding rota-vtion with respect to the nut or the engaged members surface 52 andindependent rotation of the nut may be continued until the specifieddegree of torque has been applied thereto, as dictated by the tightnessdesired in the joint,'the grade of bolt utilized and other variablefactors which will be obvious to those familiar with the art. As may bereadily observed from a comparison of FIGS. 3 and 4, continued turningof the nut onto the bolt, absent any further washer rotation,precipitates a discrete flattening of the spring lock washer 10 due tothe pressure exerted thereon by the skirt l6, and thus the washer exertsa reverse axial tension on the nut to lock the interengaged nut and boltthreads in the well-known manner. Further, since only the nut componentrotates during tightening of the joint, theamount of torque which mustbe applied to the nut to achieve the desired tension on the bolt issubstantially reduced. To put it in other words, during tightening thereis negative development of false or unnecessary torque which wouldotherwise result from coincident rotation of the washer against theconfronting surface 52 of the member 44. From a still closer inspectionof FIG. 4, one will observe that the progressive build up of tension inthe joint incident to the application of ultimate tightening torque tothe nut exerts an axial pull on the inner nut barrel which yieldsdownwardly to close the gap between the bearing ring and washer andprecipitates a consequent clamping of the confronting washer surface 38against the opposed surface 28 of the bearing ring. Even after thesesurfaces are placed in contact and the bearing ring surface is rotatingagainst the washer, the smooth, complementary configuration of theopposed surfaces permits continued unimpeded rotation of the nut withonly'negligible, if any, increase in the torque required to overcome theminimal increase in rotation resisting friction. Moreover, the presenceof the bearingring in the combination prevents the inner nut barrel frombeing pulled through the washer aperture as the barrel yields downwardlyresponsive to the tension build up described above, and, what is equallyif not more important, the clamping of the washer against the bearingring transfers a compressive force from the flattened spring washerdirectly to the lower and of the inner nut barrel whereby the saidbarrel end is urged inwardly and the nut thread embraces both the upperand lower faces of the mating bolt thread. When the nut is torqued up tothe point where the mating bolt is approaching its ultimate tensionalstrength, the aforementioned inward pressure on the nut barrel providesfor an effective and improved locking and resistance to loosening of thecomponents in the joint. Thus, the bearing ring 26 provides for theeffective transfer of at least a portion of the reactive tensional forcefrom the compressed spring washer directly to the inner nut barrel andthe engaged threads and contributes a functional improvement in jointsof the type disclosed, particularly wherein sheet metal components areutilized. In fact, tests conducted to date indicate that, regardless ofthe amount of torque required to generate a desired amount of tension ina mating bolt, the ultimate tension which can be derived isapproximately doubled when the bearing ring is present at an angle ofapproximately 45', as compared with an assembly wherein the inner nutbarrel does not embody a bearing ring or equivalent element. It shouldalso be noted that while the surface 28 of the bearing ring was earlierdescribed as being at a selected acute angle to the longitudinal nutaxis, the said sur- I face may not necessarily be straight, but rathermay be slightly convex while the surface 38 of the washer may becomplementarily convex, whereby frictional resistance to relativerotation is further obviated.

FIG. 7 depicts a slightly modified washer 100 which includes a pluralityof spaced projections or teeth 54 depending from the undersurfacethereof, which projections or teeth are particularly adapted for bitingengagement with the surface of a' metallic mounted member to effect anelectrical ground where required. The same projections or teeth willalso afiord additional resistance to washer rotation during nuttightening.

. By again having reference to FIGS. 3 and 4, the reader will alsoreadily appreciate that, as compared with an assembly of a headed nutdevoid of a peripheral skirt and a rotatable washer, the skirt of thesheet metal nut of the present invention provides a barrier between theconvex washer surface and the leading end of a power driven chuck. Ergo,when such a tool is utilized to tighten a nut, the skirt inhibitsundesirable scoring or marring of the washer finish beyond theperipheral edge of the nut skirt.

The modified embodiment of the invention depicted in FIGS. 8 and 9 isessentially the same as earlier described, particularly with referenceto the nut to washer connection. Further, the modified form is designedto function in the same manner in cooperation with a bolt in a joint andmay carry the alternate type of toothed lock washer depicted in FIG. 7.However, in adapting the invention to accommodate larger sizes of bolts,i.e. bolts on the order of V4 inch diameter or larger, it was observedthat during final tightening wherein the ultimate tensional strength ofthe bolt was being approached, it became somewhat difficult to deliverthe torque required to rotate the inner nut barrel through the wrenchingfaces of the outer hex barrel and the other barrel frequently shearedaway from the tubular inner barrel at the connecting web. Responsive tofurther experimentation, it was discovered that the aforementionedproblem in larger sizes could be negated by providing a hex-shapeddepression 56 in the upper end of the inner nut barrel 4b during theprocess of nut formation and prior to the tapping of the said barrel.There are several reasons why the formation of the hex depression 56 isseen to strengthen the nut and increase its torsional resistance toshearing at the web. To begin with, one will readily appreciate that thecompacting of the metal, incident to depression formation, work hardensthe metal to impart increased strength in the critical area. Further, asis best depicted in FIG. 9, the metal at the internal wall of the hexdepression is displaced outwardly of the path of the threading tap, ergoonly partial, if any, thread is formed in the depression andconsequently there is negligible weakening of the wall adjacent the web.Still further, and perhaps most significant, is the fact that theinternal hex depression provides positive driving faces in the inner nutbarrel adjacent the web, which faces oppose and match the hex wrenchingfaces on the outer barrel and thus reduce the torsional strain on thebarrel connecting web incident to ultimate tightening.

Having considered the foregoing detailed description, one who now refersback to the United-Carr Fastener (hereinafter called UCF) and Heller 079patents earlier mentioned will readily recognize the improvements in theart which are the contribution of the present disclosure and in whichinvention is seen to abide.

In the UCF teaching, which discloses a double barreled, sheet metal nutin the assembly, there exists an obvious lack of any upper supporting orbearing element for the portion 9 of the washer 6. Further, theconnecting elements of the nut and washer intersect at substantiallyright angles and relatively sharp comers which provide possibleimpediments to independent rotation or potential increased frictionalresistance to turning of the nut. Another important aspect of thepresent invention which is best understood by a comparison with the UCFdisclosure is that a substantial narrowing of the space between theinner and outer barrel portions even to the point that they areabutting, as is frequently the case with larger size nuts requiringthicker material and an enlarged inner barrel, has no adverse afiect onthe nut to washer connection or the relative free spinning capabilitiesof the present components, whereas a similar narrowing of the spacingbetween the inner and outer barrels in UCF would cause a rotationinhibiting, jamming or binding of the washer portion 9. Obviously, itfollows that the required spacing which must be maintained in the UCFnut gives rise to increased production costs by reason of the additionalstock which must be used in fabricating larger sized nuts to be coupledto the washer in the manner disclosed therein. I

The Heller 079 disclosure of a single walled sheet metal nut with asingle helix thread form is also considered deficient in that theassembly lacks any bearing ring or other upper support for tubularportion 32 of the washer. Further, the Heller nut to washer connectioncertainly does not recommend itself for use with a double barreled nutof the present type in that excessively wide spacing between the nutbarrels would be required to receive the preflared end of the tubularwasher portion 32, or a swaging or flaring tool which would have to passbetween the nut barrels to curl the washer over the dimple 36 of the nutif the washer were first inserted in a perfectly tubular condition.

The reader, who should now have a clear understanding of the merits ofthe present disclosure, should proceed to refer to the claims whichfollow for a more precise definition of the scope of the inventionprotected by these Letters Patent.

1. In a fastener assembly of the type wherein a nut is rotatablyconnected to a washer, and wherein the nut is of sheet metalconstruction and includes an inner threaded barrel portion, an outerbarrel portion joined to the upper end of the inner barrel portion andcircumscribing the inner barrel portion in at least partially spacedrelationship thereto and having a peripheral skirt extending outwardlyfrom its end remote from the junction with the inner barrel portion. andwherein the washer has a generally frusto-conical shape and has acentral, through aperture formed therein, and wherein the lower end ofthe inner nut barrel portion extends through the aperture in the washerand is curled under the internal edge of the washer defining theaperture to retain the parts in an assembly wherein the undersurface ofthe skirt on the outer nut barrel portion rotatably bears against theadjacent convex face of the washer; the improvement comprising aperipheral bearing ring disposed on the said inner barrel portionadjacent the lower end thereof, said ring having been formed from metaltaken from the outer wall of said inner barrel portion and compressedinto said ring formation, said ring including an undersurface lying at aselectively predetermined angle to the longitudinal axis of said nut,and said washer having an upper surface adjacent the opening therein,said surface being complementary to and in confrontation with theundersurface of said ring, the said fastener assembly providing for animproved torque-tensile relationship in effecting an attachment whereinthe fastener assembly is applied to a cooperating male fastener elementand tightened against the surface of an apertured member through whichthe male element extends.

2. A fastener assembly according to claim I wherein the saidundersurface of said bearing ring lies at an acute angle to thelongitudinal axis of said nut.

3. A fastener assembly according to claim 1 wherein the said outerbarrel portion of said nut is externally shaped for engagement by a toolfor rotating said nut.

4. A fastener assembly according to claim 3- wherein said inner barrelportion proximate the junction with said outer barrel portion has aradially enlarged depression of limited axial extent formed therein, theshape of said depression corresponding to the shape of the said outerbarrel portion.

5. A fastener assembly according to claim 4 wherein the said innerbarrel portion defined by said radially enlarged depression carries lessthan a full depth thread.

6. A fastener assembly according to claim 1 wherein the said bearingring lies substantially coplanar with the said skirt on said outer nutbarrel portion.

7. A fastener assembly according to claim 1 wherein the said bearingring has a generally triangular configuration as viewed in crosssection.

8. A fastener assembly according to claim 1 wherein the undersurface ofsaid washer is recessed adjacent the aperture therein, and the terminalportion of the lower end of said inner nut barrel portion is disposed insaid recess.

9. .A fastener assembly according to claim 1 wherein the said innerbarrel portion of said nut carries an internal, multiconvolution threadof a standard type adapted for engagement with a cooperating threadedbolt.

10. A fastener assembly according to claim 8 wherein said washerincludes a shallow lip projecting from the upper convex surface thereof,the said lip embodying the said upper surface confronting theundersurface of said bearing ring, and the said recess in theundersurfaceof said washer being disposed opposite said lip, the inboardextremities of said lip and said recess intersecting in a narrow rimdefining the edge of the through aperture in said washer, said rim beingrotatably secured to said nut and lying between the curled end of saidinner barrel portion and the undersurface of said bearing ring.

11. A fastener assembly according to claim 1 wherein said,

peripheral skirt on said outer nut barrel portion bears against alocalized area of the convex surface of said washer, said localized areabeing less than one-half the total area of the said convex surface.

12. A fastener assembly according to claim 1 wherein the said bearingring is slightly spaced from the said complementary, confronting surfaceon said washer to insure that the said peripheral skirt on said outernut barrel portion bears against the said convexsurface of the washer toprovide for effective tensioning of a cooperating male fastener elementwhen relatively low torque is applied to the nut during tightening ofthe fastener assembly against the surface of the member through whichthe male element extends.

13. In a fastener assembly of the type wherein a sheet metal nut havinginner and outer barrel portions is rotatably assembled with an aperturedwasher, and wherein said outer barrel portion embodies means rotatablybearing on said washer outwardly of the aperture therein, an improvednut to washer connection comprising a connecting collar on said innernut barrel portion which is curled under the internal edge of theaperture in the washer, said washer having a recess formed in theundersurface thereof in which portions of said collar are seated, and aperipheral bearing ring on said inner nut barrel portion disposedadjacent said collar, said bearing ring having been formed from materialtaken from said inner barrel portion and compressed into said ringconfiguration, said bearing ring having an undersurface disposed at aselectively predetermined angle to the longitudinal axis of said nut,said washer having a surface adjacent the aperture therein, said surfacelying complementary to and in confrontation with the said undersurfaceof said bearing ring, said connecting collar and bearing ringcooperating to maintain said nut and washer in a relative rotaryassembly wherein the said'components are free spinning with respect toeach other, whereby said fastener assembly is adapted to provide animproved torque-tensile relationship in a coupling wherein said fastenerassembly is turned onto a male fastener element protruding through anapertured member and tightened against the confronting surface of themember.

14. A sheet metal nut which is particularly adapted for assembly with alock washer in a rotatable combination, said nut comprising an inner,threaded barre] portion, said inner barrel portion having a free endadapted to be passed through an opening in a lock washer and flaredoutwardly beneath a surface of the washer to effect an assembly with thewasher and having a" peripheral bearing ring disposed on its outer walladjacent the said free end, said bearing ring having been formed frommetal skived from the said free end and compacted into said bearing ringconfiguration, said bearing ring generally having the shape of ahorizontally disposed letter V as viewed in cross section and presentinga surface proximate said free end which is disposed at an angle notsubstantiallv greater than 45 to the longitudinal axis of said innerbarrel portion, said surface being adapted to be brought intoconfrontation with a complementary bearing surface on a lock washer whenthe nut is assembled with the washer. and an outer barrel portion joinedto the end of said inner barrel portion remote from said free endthrough a connecting web, said outer barrel portion being disposed in atleast partially spaced, circumscribing relationship to said inner barrelportion and having a peripheral, washer engaging skirt extendinglaterally from its remote end from said web, said outer barrel portionhaving a hexagonal configuration and thus preventing six wrenchingfaces, the end of said inner barrel portion proximate said connectingweb having a hexagonal depression of limited axialextent formed thereinand presenting six faces opposite to and matching the said wrenchingface, said hexagonal section of said inner barrel portion beingeffective to transmit torque from said outer barrel portion to saidinner barrel portion when said nut is turned onto a mating-bolt with atool engaging the said wrenching faces on said outer barrel portion andto reduce the torsional strain on said connecting web incident toultimate tightening of said nut on a bolt.

1. In a fastener assembly of the type wherein a nut is rotatablyconnected to a washer, and wherein the nut is of sheet metalconstruction and includes an inner threaded barrel portion, an outerbarrel portion joined to the upper end of the inner barrel portion andcircumscribing the inner barrel portion in at least partially spacedrelationship thereto and having a peripheral skirt extending outwardlyfrom its end remote from the junction with the inner barrel portion, andwherein the washer has a generally frusto-conical shape and has acentral, through aperture formed therein, and wherein the lower end ofthe inner nut barrel portion extends through the aperture in the washerand is curled under the internal edge of the washer defining theaperture to retain the parts in an assembly wherein the undersurface ofthe skirt on the outer nut barrel portion rotatably bears against theadjacent convex face of the washer; the improvement comprising aperipheral bearing ring disposed on the said inner barrel portionadjacent the lower end thereof, said ring having been formed from metaltaken from the outer wall of said inner barrel portion and compressedinto said ring formation, said ring including an undersurface lying at aselectively predetermined angle to the longitudinal axis of said nut,and said washer having an upper surface adjacent the opening therein,said surface being complementary to and in confrontation with theundersurface of said ring, the said fastener assembly providing for animproved torque-tensile relationship in effecting an attachment whereinthe fastener assembly is applied to a cooperating male fastener elementand tightened against the surface of an apertured member through whichthe male element extends.
 2. A fastener assembly according to claim 1wherein the said undersurface of said bearing ring lies at an acuteangle to the longitudinal axis of said nut.
 3. A fastener assemblyaccording to claim 1 wherein the said outer barrel portion of said nutis externally shaped for engagement by a tool for rotating said nut. 4.A fastener assembly according to claim 3 wherein said inner barrelportion proximate the junction with said outer barrel portion has aradially enlarged depression of limited axial extent formed therein, theshape of said depression corresponding to the shape of the said outerbarrel portion.
 5. A fastener assembly according to claim 4 wherein thesaid inner barrel portion defined by said radially enlarged depressioncarries less than a full depth thread.
 6. A fastener assembly accordingto claim 1 wherein the said bearing ring lies substantially coplanarwith the said skirt on said outer nut barrel portion.
 7. A fastenerassembly according to claim 1 wherein the said bearing ring has agenerally triangular configuration as viewed in cross section.
 8. Afastener assembly according to claim 1 wherein the undersurface of saidwasher is recessed adjacent the aperture therein, and the terminalportion of the lower end of said inner nut barrel portion is disposed insaid recess.
 9. A fastener assembly according to claim 1 wherein thesaid inner barrel portion of said nut carries an internal,multiconvolution thread of a standard type adapted for engagement with acooperating threaded bolt.
 10. A fastener assembly according to claim 8wherein said washer includes a shallow lip projecting from the upperconvex surface thereof, the said lip embodying the said upper surfaceconfronting the undersurface of said bearing ring, and the said recessin the undersurface of said washer being disposed opposite said lip, theinboard extremities of said lip and said recess intersecting in a narrowrim defining the edge of the through aperture in said washer, said rimbeing rotatably secured to said nut and lying between the curled end ofsaid inner barrel portion and the undersurface of said bearing ring. 11.A fastener assembly according to claim 1 wherein said peripheral skirton said outer nut barrel portion bears against a localized area of theconvex surface of said washer, said localized area being less thanone-half the total area of the said convex surface.
 12. A fastenerassembly according to claim 1 wherein the said bearing ring is slightlyspaced from the said complementary, confronting surface on said washerto insure that the said peripheral skirt on said outer nut barrelportion bears against the said convex surface of the washer to providefor effective tensioning of a cooperating male fastener element whenrelatively low torque is applied to the nut during tightening of thefastener assembly against the surface of the member through which themale element extends.
 13. In a fastener assembly of the type wherein asheet metal nut having inner and outer barrel portions is rotatablyassembled with an apertured washer, and wherein said outer barrelportion embodies means rotatably bearing on said washer outwardly of theaperture therein, an improved nut to washer connection comprising aconnecting collar on said inner nut barrel portion which is curled underthe internal edge of the aperture in the washer, said washer having arecess formed in the undersurface thereof in which portions of saidcollar are seated, and a peripheral bearing ring on said inner nutbarrel portion disposed adjacent said collar, said bearing ring havingbeen formed from material taken from said inner barrel portion andcompressed into said ring configuration, said bearing ring having anundersurface disposed at a selectively predetermined angle to thelongitudinal axis of said nut, said washer having a surface adjacent theaperture therein, said surface lying complementary to and inconfrontation with the said undersurface of said bearing ring, saidconnecting collar and bearing ring cooperating to maintain said nut andwasher in a relative rotary assembly wherein the said components arefree spinning with respect to each other, whereby said fastener assemblyis adapted to provide an improved torque-tensile relationship in acoupling wherein said fastener assembly is turned onto a male fastenerelement protruding through an apertured member and tightened against theconfronting surface of the member.
 14. A sheet metal nut which isparticularly adapted for assembly with a lock washer in a rotatablecombination, said nut comprising an inner, threaded barrel portion, saidinner barrel portion having a free end adapted to be passed through anopening in a lock washer and flared outwardly beneath a surface of thewasher to effect an assembly with the washer and having a peripheralbearing ring disposed on its outer wall adjacent the said free end, saidbearing ring having been formed from metal skived from the said free endand compacted into said bearing ring configuration, said bearing ringgenerally having the shape of a hoRizontally disposed letter ''''V''''as viewed in cross section and presenting a surface proximate said freeend which is disposed at an angle not substantially greater than 45* tothe longitudinal axis of said inner barrel portion, said surface beingadapted to be brought into confrontation with a complementary bearingsurface on a lock washer when the nut is assembled with the washer, andan outer barrel portion joined to the end of said inner barrel portionremote from said free end through a connecting web, said outer barrelportion being disposed in at least partially spaced, circumscribingrelationship to said inner barrel portion and having a peripheral,washer engaging skirt extending laterally from its remote end from saidweb, said outer barrel portion having a hexagonal configuration and thuspreventing six wrenching faces, the end of said inner barrel portionproximate said connecting web having a hexagonal depression of limitedaxial extent formed therein and presenting six faces opposite to andmatching the said wrenching face, said hexagonal section of said innerbarrel portion being effective to transmit torque from said outer barrelportion to said inner barrel portion when said nut is turned onto amating bolt with a tool engaging the said wrenching faces on said outerbarrel portion and to reduce the torsional strain on said connecting webincident to ultimate tightening of said nut on a bolt.